Thank you again, Raze!
Yes, I have the latest (1.0034) patch but still caught this problem. Can't say when or how, but it's very possible I got my Magic Barrier ring before learning the skill. Didn't lose more than a few steps so it was easily recovered with that save editor. I'll try keeping the skill but ditching the ring (and avoiding any other items with that skill).

I compared a bit with old saves and it looks like my sight range is correct - I just got too exited and bought too many steps. And of course my equipment adds some too. I'll try change some gear and just live with the choices I made.

Again, thanks for the help!